The present invention relates to a recording apparatus, a recording method, a reproducing apparatus, a reproducing method, and a record medium that allow a volume label of a record medium such as a magnetic tape on which data is sequentially recorded and reproduced to be read at high speed.
In a computer system, a changer apparatus that accommodates many cassette cartridges has been used to accomplish a data library. In the changer apparatus, several ten to several thousand cassette cartridges are placed in designated positions of a bin. In addition, at least one recording/reproducing apparatus (tape drive) is built in the changer apparatus. The changer apparatus is connected to a host computer that operates on UNIX as an OS (Operating System) through SCSI (Small Computer System Interface) as an interface.
The host computer has a database for managing the data library. The database contains information about cassette cartridges accommodated in the changer apparatus. The cassette cartridges are managed as volumes. The cassette cartridges are identified with bar codes placed thereon and volume labels recorded in predetermined record areas thereof.
The changer apparatus has a bar code reader and a cassette cartridge conveying mechanism. The bar code reader reads a bar code from a cassette cartridge. The cassette cartridge conveying mechanism automatically conveys a designated cassette cartridge to a designated recording/reproducing apparatus. When particular data is designated, the host computer searches the library management database for a relevant volume. Corresponding to the designated volume, the changer apparatus automatically searches a relevant cassette cartridge and attaches the cassette cartridge to a relevant tape drive.
When the cassette cartridge is attached to the tape drive, it is determined whether or not the cassette cartridge matches the designated volume. In other words, the tape drive reads the volume label at a predetermined position of the magnetic tape. Thereafter, it is determined whether or not the content of the volume label matches the value of the bar code. When they match, the volume is mounted to the system. Thus, the system can read and write data from/to the volume.
Conventionally, a volume label is written at only the beginning end of each volume. Thus, when a volume is mounted, it is necessary to seek the position of the volume label. Consequently, it takes a long time after a volume label is read until the volume is mounted.
For example, in the case that a cassette cartridge that has not been rewound from the last write position is accommodated to the bin of the changer, when the tape is used next time, the tape should be rewound to the beginning and then the volume label should be sought.
Therefore, an object of the present invention is to provide a recording apparatus, a recording method, a reproducing apparatus, a reproducing method, and a record medium that allow a volume of a sequential medium to be mounted at high speed.
To solve the above-described problem, the present invention is a recording apparatus for mounting a volume composed of a sequential record medium and recording data thereto, comprising a current position detecting means for detecting the curent seek-position of the volume, and a volume label writing means for writing to the last data position of the volume a second volume label whose content is the same as the content of a first volume label recorded on the beginning end side of the volume and adapted for identifying the volume, when the volume is unmounted, if the current-seek position detected by the current position detecting means is the last data position of the volume.
In addition, the present invention is a reproducing apparatus for mounting a volume composed of a sequential record medium and reproducing data therefrom, comprising a current position detecting means for detecting the current seek-position of the volume, and a volume label reading means for reading a first volume label or a second volume label whichever closer corresponding to the current seek-position detected by the current position detecting means when the volume is mounted, the first volume label and the second volume label being placed on the beginning end side and the last end side of the volume, respectively, the content of the first volume label being the same as the content of the second volume label, the first volume label being adapted for identifying the volume.
In addition, the present invention is a recording method for mounting a volume composed of a sequential record medium and recording data thereto, comprising the steps of (a) detecting the curent seek-position of the volume, and (b) writing to the last data position of the volume a second volume label whose content is the same as the content of a first volume label recorded on the beginning end side of the volume and adapted for identifying the volume, when the volume is unmounted, if the current-seek position detected at step (a) is the last data position of the volume.
In addition, the present invention is a reproducing method for mounting a volume composed of a sequential record medium and reproducing data therefrom, comprising the steps of (a) detecting the current seek-position of the volume, and (b) reading a first volume label or a second volume label whichever closer corresponding to the current seek-position detected at step (a) when the volume is mounted, the first volume label and the second volume label being placed on the beginning end side and the last end side of the volume, respectively, the content of the first volume label being the same as the content of the second volume label, the first volume label being adapted for identifying the volume.
In addition, the present invention is a record medium on which data is sequentially recorded and reproduced, wherein volume labels for identifying a volume are placed on the beginning end side and the last end side of the volume.
As described above, according to the recording apparatus and the recording method of the present invention, when data is recorded to a mounted volume and then the volume is unmounted, the current seek-position is detected. When the current seek-position is the last data position, the second volume label whose content is the same as the content of the first volume label placed on the beginning end side of the volume is written to the last data position. Thus, the same volume labels can be placed on the beginning end side and the last end side of the volume.
In addition, according to the reproducing apparatus and the reproducing method of the present invention, when a volume is mounted, the current seek-position is detected. Corresponding to the detected position, the first volume label placed on the beginning end side of the volume or the second volume label (that is the same as the first volume label) placed on the last end side of the volume whichever closer is read. Thus, the volume label can be read at high speed.
According to the record medium of the present invention, since volume labels adapted for identifying a volume are placed on the beginning end side and the last end side of the volume, they can be read at high speed. In addition, the reliability of the record medium is improved.